Lining for pebble-mills.



No. 858,129. PATENTE-D JUNE 25, 1907. M. F. ABBE.

LINING FOR PEBBLE MILLS. APPLICATION FILED N0.V.1, 1906.

Fly. Z

MAX F. ABBE, OF'NEW YORK, N. Y.

LINING FOR PEBBLE -MILLS.

Specification of Letters Patent.

Patented June 1907" Application filed November 1, 1906. Serial No. 341,570.

To all whom, it may concern.-

Be it known that I, MAX F. ABBE, a citizen of the United States, residing at New York city, (Manhattan,) county and State of New York, have invented new and useful Improvements in Linings for Pebble-Mills, of which the following is a specification.

This invention relates to a lining for pebble mills of the class in which natural lining stones are employed. The stones adapted for this purpose are very hard and are out only to a rough contour. In lining a mill with these stones, the Portland cement used as the binding material, assumes the additional function of closing up the cavities between the stones. But the comparatively large body of cement required for this purpose takes a long time to-set, and while setting within the mill, necessitates that the latter be placed out of commission for a corresponding length of time. If the mill is restarted before the pro er time, the insufiiciently set cement will e quickly ground out of the joints, thus requiring frequent relining.

By my invention the above objections are overcome, the stones being so prepared prior to their introduction into the mill, that any extended period required for the setting of the cement within the mill is entirely obviated.

In the accompanying drawing: Figure 1 is a front elevation, partly in section, of my improved pebble mill; Fig. 2 an enlarged cross section of part of the same; Fig. 3 a perspective view of one of the lining blocks; Fig. 4 a cross section on line 4 4, Fig. 3, and Fig. 5 a longitudinal section on line 55, Fig. 3.

A natural stone 10, such as silex, is roughly cut approximately into the shape desired. The crevices and cavities in each side of the stone are filled out by a thinlayer 11, 'of Portland cement, so as to obtain a smooth surface. In like manner the crevices and cavities in the ends of the stone are filled out by the cement layers 12. layers 11 and 12, the stone is provided with a cement backing 13, which is however considerably thicker than layers 11 and 12. The

In addition to the cement covering above described is ap lied to the stone in a mold, and is of such a s ape that side layers 11,will taper, while end layers 12, will be parallel to each other. The exposed surface of backing 13 is preferably flat. 5 5 After the stone has been supplemented in the manner described, to assume the shape and even outline desired, it is removed from the mold, and the cement is permitted to set. After this setting the stone is preferably stored under water fora period that may extend over months, so that the cement will thoroughly harden and thus form an envelop of hardened cement at the sides, ends and back of the stone. This storing may be accomplished without inconvenience, as the stones do not as yet form part of the mill.

When the cylindricalgrinding chamber 14 of the mill is to be lined, the true and sea soned stones, prepared'as described, are readily fitted into the same, so that the time during which the mill is out of commission, is reduced to a minimum. In applying the lining, the inner surface of cylinder 14 is covered with cement, and then the prepared stones are pressed against the cylinder-wall,

until their longitudinal outer edges contact with the latter. In this way the stones are readily gaged, so that their inner or working surfaces will become properly alined. The cement 15, between stones and cylinder, will be pressed into the segmental form shown, andwill readily unite with the cement backing 13. As the sides and ends of the stones are by the layers 11 and 12, made perfectly smooth and true, only an extremely thin binding layer 16, of cement, is required to connect adjoining stones. This binding layer has no longer the function of filling the crevices in the sides of the stones, and being extremely thin, is not apt to be ground out, even if not completely hardened. Thus, the mill is ready for use directly after the lining has been fitted in position, and prolongedidleness of the mill is avoided.

The cement backing 13 of the stone, permits the latter to be used up completely, or throughout its entire thickness, because it holds the stone bodily off the inner surface of adjoining coated stones to each other and the mill. In this Way thelife of the lining is prolonged and Waste is avoided.

I claim:

A cylindrical pebble mill provided with a number of natural lining stones each embedded at its sides, ends and back in a coat of hardened cement, and means for securing also to the mill, substantially as specified.

Signed by me at New York city, (Manhattan,) N. Y., this 31st day of October 1906 M A X F. ABBE.

Witnesses:

FRANK V. BRIEs'EN, ARTHUR ZUMPE. 

